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Dim artificial light at night reduces the cellular immune response of the black field cricket, Teleogryllus commodus

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Insect Science 2020年第3期27卷 571-582页

作者： Joanna Durrant mark P.green Theresa M.Jones The School of BioSciences Faculty of ScienceUniversity of MelbourneVictoria3010Australia

A functioning immune system is crucial for protection against disease and illness,yet increasing evidence suggests that species living in urban areas could be suffering from immune suppression,due to the presence of artificial light at night(ALAN).This study examined the effects of ecologically relevant levels of ALAN on three key measures of immune function(haemocyte concentration,lytic activity,and phenoloxidase activity)using a model invertebrate species,the Australian black field cricket,Teleogryllus *** reared crickets under an ecologically relevant daily light‐cycle consisting of 12 hr bright daylight(2600 lx)followed by either 12 h darkness(0 lx)or dim environmentally relevant ALAN(1,10,100 lx),and then assessed immune function at multiple time points throughout adult life using haemolymph *** found that the presence of ALAN had a clear negative effect on haemocytes,while the effects on lytic activity and phenoloxidase activity were more complex or largely unaffected by ***,the effects of lifelong exposure to ALAN of 1 lx were comparable to those of 10 and 100 *** data suggest that the effects of ALAN could be large and widespread,and such reductions in the core immune response of individuals will likely have greater consequences for fitness and survival under more malign conditions,such as those of the natural environment.

关键词： circadian rhythm ecophysiology immune function immunomodulation invertebrate light pollution melatonin urbanization

Isolation of Single-Walled Carbon Nanotube Enantiomers by Density Differentiation

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Nano Research 2009年第1期2卷 69-77页

作者： Alexander A.green Matthew C.Duch mark C.Hersam Department of Materials Science and Engineering and Department of Chemistry Northwestern UniversityEvanstonIllinois 60208-3108USA

Current methods of synthesizing single-walled carbon nanotubes(SWNTs)result in racemic mixtures that have impeded the study of left-and right-handed *** we present a method of isolating different SWNT enantiomers using density gradient *** separation is enabled by the chiral surfactant sodium cholate,which discriminates between left-and right-handed SWNTs and thus induces subtle differences in their buoyant *** sorting strategy can be employed for simultaneous enrichment by handedness and roll-up vector of SWNTs having diameters ranging from 0.7 to 1.5 *** addition,circular dichroism of enantiomer refined samples enables identification of high-energy optical transitions in SWNTs.

关键词： Carbon nanotube separation handedness enantiomer optical activity chirality

Modification Design Method for an Enveloping Hourglass Worm Gear with Consideration of Machining and Misalignment Errors

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Chinese Journal of Mechanical Engineering 2013年第5期26卷 948-956页

作者： DENG Xingqiao WANG Jinge HORSTEMEYER mark f School of Mechanical Engineering and Automation Xihua University Center for Advanced Vehicular Systems Mississippi State University

The influences of machining and misalignment errors play a very critical role in the performance of the anti-backlash double-roller enveloping hourglass worm gear(ADEHWG).However,a corresponding efficient method for eliminating or reducing these errors on the tooth profile of the ADEHWG is seldom *** gear engagement equation and tooth profile equation for considering six different errors that could arise from the machining and gear misalignment are derived from the theories of differential geometry and gear ***,the tooth contact analysis(TCA) is used to systematically investigate the influence of the machining and misalignment errors on the contact curves and the tooth profile by means of numerical analysis and three-dimensional solid *** research results show that vertical angular misalignment of the worm wheel(Δβ) has the strongest influences while the tooth angle error(Δα) has the weakest influences on the contact curves and the tooth profile.A novel efficient approach is proposed and used to minimize the effect of the errors in manufacturing by changing the radius of the grinding wheel and the approaching point of *** results from the TCA and the experiment demonstrate that this tooth profile design modification method can indeed reduce the machining and misalignment *** modification design method is helpful in understanding the manufacturing technology of the ADEHWG.

关键词： worm gears tooth contact analysis machining and misalignment errors tooth profile errors modification method

Runout of submarine landslide simulated with material point method

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Journal of Hydrodynamics 2017年第3期29卷 438-444页

作者： Youkou Dong Dong Wang mark f.Randolph Centre for Offshore foundation Systems the University of Western Australia Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of China

Most of the present knowledge on submarine landslides relies upon back-analysis of post-failure deposits identified using geophysical *** this paper,the runout of slides on rigid bases is explored using the material point method（MPM）with focus on the geotechnical aspects of the *** MPM,the sliding material and bases are discretised into a number of Lagrangian particles,and a background Eulerian mesh is employed to update the state of the *** morphologies of the slide can be reproduced by tracking the Lagrangian particles in the dynamic processes.A real case history of a submarine slide is back-analyzed with the MPM and also a depth-averaged *** of the slides from steep slopes to moderate bases are *** different combinations of soil and basal parameters are assumed to trigger runout mechanisms of elongation,block sliding and *** runout distances predicted by the MPM match well with those from large deformation finite element analysis for the elongation and block sliding *** and grabens are shaped in a spreading ***,the current MPM simulations for materials with high sensitivities are relatively mesh sensitive.

关键词： Submarine landslide runout morphology material point method large deformation

Improved estimation of PM_(2.5) brown carbon contributions to filter light attenuation

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Particuology 2021年第3期19卷 1-9页

作者： Judith C.Chow L.-W.Antony Chen Xiaoliang Wang mark C.green John G.Watson Division of Atmospheric Sciences Desert Research InstituteRenoNVUSA State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’anChina Graduate faculty Department of Atmospheric SciencesUniversity of NevadaReno NevadaUSA Department of Environmental and Occupational Health School of Public HealthUniversity of NevadaLas VegasNVUSA

Multiwavelength light attenuation measurements have been acquired as part of thermal/optical carbon analysis in the *** Speciation Network(CSN)and the Interagency Monitoring of PROtected Visual Environments(IMPROVE)network beginning in *** are used to estimate PM_(2.5)brown carbon(BrC)contributions to light absorption at various wavelengths,a useful method for separating biomass burning contributions from other *** of light transmitted through the filter deviates from Beers Law as the mass of light absorbing materials *** study estimates the effects of these deviations with empirical adjustment factors applied to samples for CSN from 2016 to 2017 and for IMPROVE from 2016 to *** for the filter loading effect results in an annual average increase of∼6-7%BrC contribution to light attenuation:from 3.6%to 10.7%for the urban,more heavily loaded CSN samples;and from 23.7%to 29.5%for the non-urban IMPROVE *** alternative method is examined for BrC and black carbon(BC)adjustments by calculating the AbsorptionÅngström Exponent(AAE)for BC(i.e.,AAE_(BC))based on the ratios of 635 nm/780 nm light attenuation rather than assuming AAE_(BC)of *** paired-wavelength calculations result in a median AAE_(BC)of 0.76 for CSN and 0.8 for IMPROVE,with the majority of samples(i.e.,91%of CSN and 70%of IMPROVE)showing AAE_(BC)from BrC to AAE at longer wavelengths,the amount of light attenuation at shorter wavelengths(e.g.,405 nm)where BrC is dominant can be *** paired-wavelength method applied to the filter loading adjusted data has a greater effect on urban(fresh)than on non-urban(aged)aerosols,resulting in a factor of two increase in annual averaged BrC light attenuation(from 10.7%to 21.6%)for CSN and by a factor of 1.11(from 29.5%to 32.7%)for IMPROVE *** result demonstrates the importance of particle loading and AAE correction on quantifying BrC light attenuatio

关键词： Organic carbon Brown carbon Elemental carbon Black carbon AbsorptionÅngström Exponent

Quantification of ventilation enhancement using the Eye CAN roof support

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International Journal of Mining Science and Technology 2017年第1期27卷 153-158页

作者： Shook Michael T Sindelar mark f, Jiang Hua Luo Yi Burrell Mining Products Inc.New KensingtonPA 15068USA Department of Mining Engineering West Virginia UniversityMorgantownWV 26506USA

Convergence of roof and floor in underground mine openings is a common occurrence. This convergence not only adversely affects the ability of workers, equipment and supplies to travel through the mine, it also reduces the effectiveness of the mine ventilation system, which is essential for the dilution of methane gas and airborne respirable dust. While installing secondary standing supports to control floor and roof convergence, such supports, by nature, partially obstruct a portion of the airway. These added obstructions inhibit the ability of the ventilation system to operate as efficiently as it could by increasing the resistance in and reducing the cross-sectional area of the airway. This study introduces and demonstrates the benefits of The Eye CAN^(TM) standing roof support, which controls floor and roof convergence and is less obstructive to air flow than conventional wooden cribs. Laboratory findings show that the normal resistance of a supported lined airway is reduced by using this new product from Burrell Mining Products, Inc., while providing the same roof support characteristics of an established product—The CANò. Load vs. displacement curves generated from laboratory tests demonstrated that this new product behaves with the same roof support characteristics as others in The CAN product family. Ventilation data gathered from a simulated mine entry was then used for computational fluid dynamics(CfD) *** CfD analysis showed an improvement with The Eye CAN vs. other accepted forms of standing roof support. This proof-of-concept study suggests that, when using this new product made by Burrell Mining Products, Inc., not only will the convergence from the roof and floor be controlled, but airway resistance will also be reduced.

关键词： Standing roof support CAN Ventilation Load-displacement Eye CAN

Capsule endoscopy:Current practice and future directions

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World Journal of Gastroenterology 2014年第24期20卷 7752-7759页

作者： Melissa f Hale Reena Sidhu mark E McAlindon Department of Gastroenterology Royal Hallamshire HospitalSheffield S10 2JFUnited Kingdom

Capsule endoscopy (CE) has transformed investigation of the small bowel providing a non-invasive, well tolerated means of accurately visualising the distal duodenum, jejunum and ileum. Since the introduction of small bowel CE thirteen years ago a high volume of literature on indications, diagnostic yields and safety profile has been presented. Inclusion in national and international guidelines has placed small bowel capsule endoscopy at the forefront of investigation into suspected diseases of the small bowel. Most commonly, small bowel CE is used in patients with suspected bleeding or to identify evidence of active Crohn’s disease (CD) (in patients with or without a prior history of CD). Typically, CE is undertaken after upper and lower gastrointestinal flexible endoscopy has failed to identify a diagnosis. Small bowel radiology or a patency capsule test should be considered prior to CE in those at high risk of strictures (such as patients known to have CD or presenting with obstructive symptoms) to reduce the risk of capsule retention. CE also has a role in patients with coeliac disease, suspected small bowel tumours and other small bowel disorders. Since the advent of small bowel CE, dedicated oesophageal and colon capsule endoscopes have expanded the fields of application to include the investigation of upper and lower gastrointestinal disorders. Oesophageal CE may be used to diagnose oesophagitis, Barrett’s oesophagus and varices but reliability in identifying gastroduodenal pathology is unknown and it does not have biopsy capability. Colon CE provides an alternative to conventional colonoscopy for symptomatic patients, while a possible role in colorectal cancer screening is a fascinating prospect. Current research is already addressing the possibility of controlling capsule movement and developing capsules which allow tissue sampling and the administration of therapy.

关键词： Capsule endoscopy Small bowel Indications Technology Oesophageal Colon

Effect of process parameters on the density and porosity of laser melted AlSi10Mg/SiC metal matrix composite

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frontiers of Mechanical Engineering 2018年第4期13卷 520-527页

作者： Omotoyosi H. fAMODIMU mark STANfORD Chike f. ODUOZA Lijuan ZHANG faculty of Science and Engineering School of Engineering Telford Campus University of Wolverhampton WV1 1LY Wolverhampton UK

Laser melting of aluminium alloy-AlSi10Mg has increasingly been used to create specialised products in various industrial applications, however, research on utilising laser melting of aluminium matrix composites in replacing specialised parts have been slow on the uptake. This has been attributed to the complexity of the laser melting process, metal/ceramic feedstock for the process and the reaction of the feedstock material to the laser. Thus, an understanding of the process, material microstructure and mechanical properties is important for its adoption as a manufacturing route of aluminium metal matrix composites. The effects of several parameters of the laser melting process on the mechanical blended composite were thus investigated in this research. This included single track formations of the matrix alloy and the composite alloyed with 5% and 10% respectively for their reaction to laser melting and the fabrication of density blocks to investigate the relative density and porosity over different scan speeds. The results from these experiments were utilised in determining a process window in fabricating near-fully dense parts.

关键词： selective laser melting additive manufacturing mechanical alloying powder metallurgy aluminium metal matrix composite

Analysis of gateroad stability at two longwall mines based on field monitoring results and numerical model analysis

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International Journal of Mining Science and Technology 2019年第1期29卷 35-43页

作者： Gabriel S.Esterhuizen David f.Gearhart Ted Klemetti Heather Dougherty mark van Dyke National Institute for Occupational Safety and Health

Coal mine longwall gateroads are subject to changing loading conditions induced by the advancing longwall face. The ground response and support requirements are closely related to the magnitude and orientation of the stress changes, as well as the local geology. This paper presents the monitoring results of gateroad response and support performance at two longwall mines at a 180-m and 600-m depth of *** the first mine, a three-entry gateroad layout was used. The second mine used a four-entry, yieldabutment-yield gateroad pillar system. Local ground deformation and support response were monitored at both sites. The monitoring period started during the development stage and continued during first panel retreat and up to second panel retreat. The two data sets were used to compare the response of the entries in two very different geotechnical settings and different gateroad layouts. The monitoring results were used to validate numerical models that simulate the loading conditions and entry response for these widely differing conditions. The validated models were used to compare the load path and ground response at the two mines. This paper demonstrates the potential for numerical models to assist mine engineers in optimizing longwall layouts and gateroad support systems.

关键词： Coal mining Longwall Gateroad Support Numerical models